As the conventional valve timing controller, there can be mentioned a controller in which a torsion spring is provided between a driving-side rolling body and a driven-side rolling body. The torsion spring is provided for the purpose of, for example, canceling out a force in a retard direction acting on a camshaft so as to enhance responsiveness of phase variation of the camshaft, during the operation of an internal combustion engine.
Meanwhile, there are some cases in which a sealing member provided between the driving-side rolling body and the driven-side rolling body for the purpose of creating an advance chamber and a retard chamber. The sealing members are provided, for example, at positions in respective rolling bodies where two rolling bodies face each other. During the relative rotation of the two rolling bodies, even when the distance between the two rolling bodies is changed, each sealing member should firmly seal the gap between the rolling bodies with the use of a biasing spring or the like. However, in order to further enhance a sealing function of the sealing member, center alignment of the two rolling bodies should be performed at portions other than the sealing members.
In such a valve timing controller, in order to perform the center alignment of each member, the camshaft constitutes a component for the alignment. To put it another way, until all of the components are assembled, the center alignment of the driving-side rolling body and the driven-side rolling body is not performed.
The driving-side rolling body and the driven-side rolling body are assembled prior to the connection with the camshaft. Upon the assembly, in order to set the driving-side rolling body and the driven-side rolling body in an initial phase, a torsional torque has to be imparted to the torsion spring to some extent. Therefore, in the valve timing controller of such a type, various efforts have been made in order to firmly perform the connecting work of the camshaft, the center alignment work between the driving-side rolling body and the driven-side rolling body, or the like.
For example, in a case of a valve timing controller described in Patent Document 1, a bush is pressed into a vane rotor as driven-side rolling body. The bush has a function of retaining the vane rotor and a shoe housing as the driving-side rolling body on the same axis. The bush functions also as seat for receiving a bolt for connecting the camshaft to the vane rotor. The reason for this configuration of pressing the bush into the vane rotor is to accurately align the vane rotor with the bush.